What is effect of cat on A/F using wideband O2?
Thread Starter
Teching In
Joined: Dec 2004
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What is effect of cat on A/F using wideband O2? When on a dyno using an up the tailpipe wideband O2 sniffer what is typical effect on A/F ratio of a catalytic converter?
Is there a rule of thumb for this?
Paul
Is there a rule of thumb for this?
Paul
Not a dumb question. Next time I dyno I will compare my wideband to the dyno wideband to see what the difference is. Either that or i'll try the wideband in the precat and post cat o2 bungs on the same tune. Might not be for a while though.
TECH Enthusiast
Joined: Sep 2004
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From: Omaha, NE
In the mediam to high RPM at WOT, we have never noticed a measureable difference. This potentially occurs for these reasons, the CATs are designed to operate at a 14.7:1 A/F ratio for proper catylitic action and we should be more rich and the exhaust gas volume/velocity is too much for the CATS to do anything measureable. As far as using two different wide bands for a before/after CAT test, I think the two widebands could each read slightly differently skewing your results. EJ
